Yawns are more contagious among people with closer relationships.
163
Enamel is hardest substance in the human body.
61
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197